WO2020062923A1

WO2020062923A1 - Wireless charging receiving circuit, control method and terminal device

Info

Publication number: WO2020062923A1
Application number: PCT/CN2019/090428
Authority: WO
Inventors: 裴昌盛
Original assignee: 华为技术有限公司
Priority date: 2018-09-30
Filing date: 2019-06-06
Publication date: 2020-04-02
Also published as: KR102519512B1; US11870293B2; JP2022501996A; JP7150156B2; CN109462289A; CN109462289B; EP3846317A4; US20210218264A1; KR20210060566A; EP3846317A1

Abstract

A wireless charging receiving circuit, a control method and a terminal device, which relate to the field of wireless charging, and are used for compensating, when a transmission distance between a secondary coil in the wireless charging receiving circuit and a primary coil in a corresponding wireless charging sending circuit is greatly increased, for a decrease in the output voltage and output power of the wireless charging receiving circuit to a certain extent. The wireless charging receiving circuit comprises: N groups of capacitor switching networks (200), a rectification circuit (300), and a controller (CTRL), wherein N is an integer greater than or equal to one; a first end of each group of the capacitor switching networks (200) is connected to a first input end of the rectification circuit (300), and a second end of each group of the capacitor switching networks (200) is connected to a second input end of the rectification circuit (300); and the controller (CTRL) comprises N output ends, the N output ends correspond to the N groups of the capacitor switching networks (200) on a one-to-one basis, and each of the output ends is used for connecting to a control end of a first controllable switching device (Sn) located in a corresponding group of the capacitor switching networks (200) and a control end of a second controllable switching device (Sn') located in the corresponding group of the capacitor switching networks (200).

Description

Wireless charging receiving circuit, control method and terminal equipment

This application claims the priority of a Chinese patent application filed on September 30, 2018 with the State Intellectual Property Office, application number 201811161343.0, and application name "A Wireless Charging Receiving Circuit, Control Method, and Terminal Equipment", all of which passed Citations are incorporated in this application.

Technical field

The present application relates to the field of wireless charging, and in particular, to a wireless charging receiving circuit, a control method, and a terminal device.

Background technique

As shown in Figure 1, it is a schematic diagram of a wireless charging principle. The wireless charging system includes a wireless charging transmitting circuit 101 and a wireless charging receiving circuit 102. In one implementation manner, wireless energy transmission can be performed between the wireless charging transmitting circuit 101 and the wireless charging receiving circuit 102 through a magnetic induction method. For example, the wireless charging transmitting circuit 101 includes an AC power source Vs, a primary series resonant capacitor Cp, and a primary coil Lp, and the wireless charging receiving circuit 102 includes a secondary coil Ls, a secondary series resonant capacitor Cs, and a rectifier circuit 1021. The AC power source Vs outputs AC power of a certain frequency, and generates a specific frequency AC power through series resonance between the primary series resonance capacitor Cp and the primary coil Lp, and wirelessly transmits energy to wireless charging through magnetic induction between the primary coil Lp and the secondary coil Ls. Receiving circuit 102. A series resonance between the secondary coil Ls and the secondary series resonance capacitor Cs generates an alternating current of an operating frequency, and the rectifying circuit 1021 converts the input alternating current of the operating frequency into a direct current, thereby driving the load RL.

The coupling efficiency between the primary coil Lp and the secondary coil Ls is related to the transmission distance between the primary coil Lp and the secondary coil Ls. When the transmission distance between the primary coil Lp and the secondary coil Ls increases, the coupling efficiency between the primary coil Lp and the secondary coil Ls decreases, which results in a decrease in the output voltage and output power of the rectifier circuit 1021.

In the prior art, one way is to reduce the operating frequency of the AC power input from the wireless charging receiving circuit 102 side by reducing the frequency of the AC power output from the wireless charging transmitting circuit 101 side, thereby improving the wireless charging receiving circuit 102 side rectifying circuit Output voltage and output power to compensate for the decrease in output voltage and output power caused by the increase in transmission distance on the wireless charging receiving circuit 102 side. However, for a wireless charging system using a wireless power transmission (WPC) protocol, the adjustment range of the AC frequency on the wireless charging transmitting circuit 101 side is limited, so the transmission distance between the primary coil Lp and the secondary coil Ls is relatively small. When it is large, the adjustment range of the operating frequency of the AC power input from the rectifier circuit on the wireless charging receiving circuit 102 side is also limited, so that the adjustment range of the output voltage and output power of the rectifier circuit on the wireless charging reception circuit 102 side is also limited.

Summary of the Invention

The present application provides a wireless charging receiving circuit for charging wirelessly to a certain extent when a transmission distance between a secondary coil in the wireless charging receiving circuit and a primary coil in a corresponding wireless charging transmitting circuit is large. The operating frequency of the AC power input from the rectifier circuit on the receiving circuit side is adjusted.

In addition, the present application also provides a control method for controlling the wireless charging receiving circuit and a terminal device using the wireless charging receiving circuit.

To achieve the above purpose, the embodiments of the present application adopt the following technical solutions:

In a first aspect, an embodiment of the present application provides a wireless charging receiving circuit, including: N sets of capacitor switching networks, a rectifier circuit, and a controller, where N is an integer greater than or equal to 1. A first end of each group of capacitor switch networks is connected to a first input terminal of a rectifier circuit, and a second end of each group of capacitor switch networks is connected to a second input terminal of a rectifier circuit. Each group of capacitor switching networks includes a first capacitor, a second capacitor, a first controllable switching device, a second controllable switching device, and a ground point. A first capacitor located on one side of the ground point is connected in series with the first controllable switching device, and a second capacitor located on the other side of the ground point is connected in series with the second controllable switching device. Wherein, the capacitance value of the first capacitor and the capacitance value of the second capacitor in the same group of capacitor switch networks are equal or substantially equal.

The controller includes N output terminals, and the N output terminals have a one-to-one correspondence with the N groups of capacitive switch networks. Each output terminal is used for the control terminal of the first controllable switching device located in the corresponding group of capacitor switch networks. Connected to the control terminal of the second controllable switching device.

The controller is configured to obtain an operating frequency of an AC voltage between the first input terminal and the second input terminal of the rectifier circuit.

When the operating frequency is less than the first frequency threshold and the capacitance of the capacitors connected to the wireless charging receiving circuit in the N-group capacitor switching network is less than a preset capacitance threshold, the controller is further configured to adjust the output voltage of each output terminal. Level to control the on and off of the first controllable switching device located in each group of capacitive switching networks and the on and off of the second controllable switching device located in each group of capacitive switching networks to increase The capacitance value of the capacitors connected to the wireless charging receiving circuit in the N group capacitor switch network.

When the operating frequency is greater than the second frequency threshold, the controller is further configured to adjust the output level of each output terminal to control the on and off of the first controllable switching device located in each group of capacitor switching networks. And turning on and off of the second controllable switching device located in each group of capacitor switching networks to reduce the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N group of capacitor switching networks.

The first frequency threshold is less than or equal to the second frequency threshold.

It should be noted that the first capacitor, the second capacitor, the first controllable switching device and the second controllable switching device located in each group of capacitor switching networks are connected together in series.

Optionally, one end of the first capacitor is connected to a first input end of the rectifier circuit, the other end is connected to one end of the first controllable switching device, and the other end of the first controllable switching device is connected to the One end of the second controllable switching device, the other end of the second controllable switching device is connected to one end of the second capacitor, and the other end of the second capacitor is connected to the second input terminal of the rectifier circuit. In this case, the ground point is located between the other end of the first controllable switching device and one end of the second controllable switching device.

Optionally, one end of the first capacitor is connected to a first input end of the rectifier circuit, the other end is connected to one end of the first controllable switching device, and the other end of the first controllable switching device is connected to the One end of the second capacitor, the other end of the second capacitor is connected to one end of the second controllable switching device, and the other end of the second controllable switching device is connected to the second input terminal of the rectifier circuit. In this case, the ground point is located between the other end of the first controllable switching device and one end of the second capacitor.

Optionally, one end of the first controllable switching device is connected to a first input end of the rectifier circuit, the other end is connected to one end of the first capacitor, and the other end of the first capacitor is connected to the second capacitor. One end of the second capacitor is connected to one end of the second controllable switching device, and the other end of the second controllable switching device is connected to the second input end of the rectifier circuit. In this case, the ground point is located between the other end of the first capacitor and one end of the second capacitor.

Optionally, one end of the first controllable switching device is connected to a first input end of the rectifier circuit, the other end is connected to one end of the first capacitor, and the other end of the first capacitor is connected to the second One end of the controllable switching device, the other end of the second controllable switching device is connected to one end of the second capacitor, and the other end of the second capacitor is connected to the second input terminal of the rectifier circuit. In this case, the ground point is located between the other end of the first capacitor and one end of the second controllable switching device.

In the wireless charging receiving circuit provided by the embodiment of the present application, the N-group capacitive switch network is used in parallel, and the controller controls the on and off of the first controllable switching device located in each group of capacitive switch networks. And, the on and off of the second controllable switching device located in each group of capacitor switch network is used to control the capacitance value of the capacitor connected to the wireless charging receiving circuit in the N group of capacitor switch network. Further, when the working frequency of the alternating current input between the first input terminal and the second input terminal of the rectifier circuit is less than the first frequency threshold, controlling the increase of the capacitance of the capacitors connected to the wireless charging receiving circuit in the N-group capacitive switch network is increased. Capacitance. When the above-mentioned operating frequency is greater than the second frequency threshold, control is performed to reduce the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N-group capacitive switch network. That is, by controlling the on and off of the first controllable switching device and the second controllable switching device in each group of the N-capacitive switch network, it is possible to achieve increased access to wireless charging The capacitance of the receiving circuit or the capacitance of the wireless charging receiving circuit is reduced, so that the working frequency of the AC power input from the rectifier circuit on the wireless charging receiving circuit side can be adjusted. Therefore, the present application provides a circuit structure for conveniently controlling the operating frequency of the AC power input by the rectifier circuit.

With reference to the first aspect, in a first possible implementation manner, the controller is further configured to obtain the voltage and current output by the rectifier circuit, and obtain the output power according to the voltage and current. When the operating frequency is greater than or equal to the first frequency threshold and less than or equal to the second frequency threshold, the capacitance of the capacitor connected to the wireless charging receiving circuit in the capacitor switching network is less than a preset capacitance threshold, and the output power is less than the preset power threshold In the case of the controller, the controller is also used to adjust the output level of each output terminal, to control the on and off of the first controllable switching device located in each group of capacitive switch networks, and to be located in each group of capacitive switch networks The second controllable switching device is turned on and off to increase the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N-group capacitive switch network.

This embodiment can adjust the on and off of the first controllable switching device and the second controllable switching device in each of the N sets of capacitive switch networks according to the operating frequency and the output power of the rectifier circuit. It is possible to increase the capacitance connected to the wireless charging receiving circuit or reduce the capacitance connected to the wireless charging receiving circuit, and then to adjust the working frequency of the AC power input from the rectifier circuit on the wireless charging receiving circuit side.

With reference to the first aspect or the first possible implementation manner of the first aspect, in a second possible implementation manner, the capacitance value of the first capacitor in the i + 1th group of capacitor switch networks is the ith group of capacitor switch networks K times the capacitance value of the first capacitor, i is an integer and 1≤i≤N-1, 1≤K≤10. This embodiment provides a method for setting the capacitance value of the first capacitor and the capacitance value of the second capacitor in the N-group capacitance switch network.

With reference to the first aspect, the first possible implementation manner of the first aspect, or the second possible implementation manner of the second aspect, in a third possible implementation manner, the circuit further includes a secondary coil and a secondary series resonance. capacitance. The first end of the secondary coil is connected to the first end of the secondary series resonance capacitor, and the second end of the secondary series resonance capacitor is connected to the first end of the N-group capacitor switch network and the first input end of the rectifier circuit. The second terminal is connected to the second terminal of the N-group capacitor switch network and the second input terminal of the rectifier circuit. The secondary coil is used for coupling with the primary coil of the wireless charging transmitting circuit. The secondary series resonance capacitor is used to generate series resonance with the secondary coil. The N-group capacitor switch network is used to generate parallel resonance with the secondary series resonant capacitor and the secondary coil.

With reference to the first aspect or any one of the first to third possible implementation manners of the first aspect, in a fourth possible implementation manner, the method further includes a first filter capacitor, and a first rectifier circuit. The output terminal is connected to the first terminal of the first filter capacitor, and the second output terminal of the rectifier circuit is connected to the second terminal of the first filter capacitor. The DC power output by the rectifier circuit includes clutter. After being filtered by the first filter capacitor, it can supply power to the load.

With reference to the fourth possible implementation manner of the first aspect, in a fifth possible implementation manner, a DC / DC step-down circuit is further included. The first terminal of the first filter capacitor is connected to the first input terminal of the DC / DC step-down circuit, the second terminal of the first filter capacitor is connected to the second input terminal of the DC / DC step-down circuit, and the first terminal of the DC / DC step-down circuit is connected. An output terminal is connected to the first terminal of the load, and a second output terminal of the DC / DC step-down circuit is connected to the second terminal of the load. The DC / DC step-down circuit is used to reduce the voltage across the first filter capacitor to increase the equivalent load impedance. When adjusting the output power of the wireless charging receiving circuit, it is required to keep the output voltage as stable as possible. As mentioned earlier, when the capacitance value of the parallel resonant capacitor is increased, the voltage output by the rectifier circuit will increase, so the DC needs to be adjusted accordingly. The / DC step-down circuit makes the voltage output by the DC / DC step-down circuit (ie, the wireless charging receiving circuit) stable.

With reference to the first aspect or any one of the first to fifth possible implementation manners of the first aspect, in a sixth possible implementation manner, the method further includes a first resistor and a second resistor; the first The first terminal of the resistor is connected to the first output terminal of the rectifier circuit, the second terminal of the first resistor is connected to the first terminal of the second resistor, and the second terminal of the second resistor is connected to the second output terminal of the rectifier circuit; The first terminal is connected to the first input terminal of the controller, and the first resistor and the second resistor are used to measure the voltage output by the rectifier circuit. Generally, the voltage output by the rectifier circuit is higher than the withstand voltage value of the input terminal of the controller, so the voltage at the lead-out point is reduced to below the withstand voltage value of the input terminal of the controller through the first resistor and the second resistor.

With reference to the fifth possible implementation manner of the first aspect, in a seventh possible implementation manner, a current sampling device is further included. The current sampling device is located on the positive line or ground line between the first filter capacitor and the DC / DC step-down circuit, and the current sampling device is connected to the second input terminal of the controller and is used to measure the current output by the rectifier circuit. The current sampling device can be used to measure the current output by the rectifier circuit.

With reference to the fifth possible implementation manner of the first aspect, in an eighth possible implementation manner, a second filter capacitor is further included; between the first output end of the DC / DC step-down circuit and the first end of the load The first terminal of the second filter capacitor is connected, and the second terminal of the second filter capacitor is connected between the second output terminal of the DC / DC step-down circuit and the second terminal of the load. The second filtering capacitor is used for filtering the output current of the DC / DC step-down circuit.

In a second aspect, an embodiment of the present application provides a control method, which is applied to a circuit as in the first aspect and any implementation manner, and the method includes the following steps.

Obtain the operating frequency of the AC voltage between the first input terminal and the second input terminal of the rectifier circuit.

When the operating frequency is less than the first frequency threshold and the capacitance of the capacitors connected to the wireless charging receiving circuit in the N-group capacitor switching network is less than a preset capacitance threshold, the output level of each output terminal is adjusted to control the The first controllable switching device in each group of capacitive switch networks is turned on and off, and the second controllable switching device in each group of capacitive switch networks is turned on and off to increase N groups of capacitive switches A capacitance value of a capacitor connected to the wireless charging receiving circuit in a network.

When the operating frequency is greater than the second frequency threshold, by adjusting the output level of each output terminal, the on and off of the first controllable switching device located in each group of capacitive switch networks is controlled, and each group is located in each group. The second controllable switching device in the capacitor switch network is turned on and off to reduce the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N group of capacitor switch networks.

With reference to the second aspect, in a first possible implementation manner, the method may further include the following steps.

Obtain the voltage and current output by the rectifier circuit, and get the output power according to the voltage and current.

When the operating frequency is greater than or equal to the first frequency threshold and less than or equal to the second frequency threshold, the capacitance of the capacitor connected to the wireless charging receiving circuit in the capacitor switching network is less than a preset capacitance threshold, and the output power is less than the preset power threshold In the case of the switch, by adjusting the output level of each output terminal, the on and off of the first controllable switching device located in each group of capacitive switch networks and the second The switch device is controlled to be turned on and off to increase the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N-group capacitive switch network.

According to a third aspect, an embodiment of the present application provides a control device. The control device includes an obtaining unit and an adjusting unit. The obtaining unit is configured to obtain an operating frequency of an AC voltage between a first input terminal and a second input terminal of the rectifier circuit. When the working frequency is less than a first frequency threshold and the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N-group capacitive switch network is less than a preset capacitance threshold, the adjusting unit is configured to adjust each The output level at the output terminal controls the on and off of the first controllable switching device located in each group of capacitive switching networks, and the on and off of the second controllable switching device located in each group of capacitive switching networks Off to increase the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N group of capacitor switch networks.

When the operating frequency is greater than a second frequency threshold, the adjusting unit is further configured to adjust an output level of each output terminal, and control the conduction of the first controllable switching device located in each group of capacitor switching networks. And off, as well as the on and off of the second controllable switching device located in each group of capacitive switch network, so as to reduce the capacitance value of the capacitor connected to the wireless charging receiving circuit in the N group of capacitive switch network . The first frequency threshold is less than or equal to the second frequency threshold.

With reference to the third aspect, in a first possible implementation manner, the obtaining unit is further configured to obtain a voltage and a current output by the rectifier circuit, and obtain an output power according to the voltage and current. When the operating frequency is greater than or equal to the first frequency threshold and less than or equal to the second frequency threshold, a capacitance value of a capacitor connected to the wireless charging receiving circuit in the capacitance switch network is smaller than the preset capacitance. When the threshold value is less than the preset power threshold, the adjusting unit is further configured to adjust the output level of each output terminal to control the first controllable switching device located in each group of capacitor switching networks. Turn-on and turn-off, and turn-on and turn-off of the second controllable switching device located in each group of capacitive switch networks, so as to increase the capacitance of the N-capacitive switch network connected to the wireless charging receiving circuit. Capacitance.

In a fourth aspect, an embodiment of the present application provides a terminal device including the wireless charging receiving circuit according to the first aspect and various possible implementation manners of the first aspect.

In a fifth aspect, an embodiment of the present application provides a storage medium on which a computer program is stored. When the computer program is executed by a processor, the control method according to the second aspect and various possible implementation manners of the second aspect is implemented. .

According to a sixth aspect, an embodiment of the present application provides a control apparatus for performing the foregoing second aspect and the methods described in various possible implementation manners of the second aspect.

According to a seventh aspect, an embodiment of the present application provides a control apparatus including a processor and a memory, where the memory is used to store a program, and the processor calls the program stored in the memory to execute the foregoing second aspect and various possible implementations of the second aspect. Way described.

In an eighth aspect, an embodiment of the present application provides a computer program product, and when the computer program product runs on a control device, the control device is caused to execute the method described in the second aspect and various possible implementation manners of the second aspect.

In a ninth aspect, an embodiment of the present application provides a chip system, including: a processor, configured to support a control device to execute the second aspect and the methods described in various possible implementation manners of the second aspect.

According to a tenth aspect, an embodiment of the present application provides a wireless charging system, including a wireless charging transmitting circuit and the wireless charging receiving circuit according to the foregoing first aspect and various possible implementation manners of the first aspect, the wireless charging receiving circuit and The wireless charging transmitting circuits perform energy transmission through magnetic induction.

For the technical effects of the second aspect to the tenth aspect, reference may be made to the content of the first aspect and various possible implementation manners of the first aspect.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a wireless charging system;

FIG. 2 is a schematic diagram of another wireless charging system; FIG.

3 is a schematic diagram of a wireless charging system according to an embodiment of the present application;

4 is a schematic diagram of another wireless charging system according to an embodiment of the present application;

5 is a schematic diagram of simulation provided by an embodiment of the present application;

FIG. 6 is a schematic diagram of a change in output voltage of a wireless charging receiving circuit with a parallel resonant capacitor according to an embodiment of the present application; FIG.

FIG. 7 is a schematic diagram of another wireless charging receiving circuit output voltage changing with a parallel resonant capacitor according to an embodiment of the present application; FIG.

FIG. 8 is a schematic diagram illustrating a change in output voltage of a wireless charging receiving circuit with a parallel resonant capacitor according to another embodiment of the present application; FIG.

9 is a schematic structural diagram of a terminal device according to an embodiment of the present application;

10 is a schematic structural diagram of a wireless charging receiving circuit according to an embodiment of the present application;

11 is a schematic structural diagram of another wireless charging receiving circuit according to an embodiment of the present application;

12 is a schematic structural diagram of still another wireless charging receiving circuit according to an embodiment of the present application;

FIG. 13 is a schematic diagram of a comparison of the offset capability and efficiency between the wireless charging receiving circuit and the conventional wireless charging receiving circuit according to the embodiment of the present application; FIG.

14 is a schematic diagram showing a relationship between a driving timing of a controllable switching device (such as a MOSFET) and an output power of a wireless charging receiving circuit according to an embodiment of the present application;

15 is a first schematic flowchart of a control method according to an embodiment of the present application;

16 is a second schematic flowchart of a control method according to an embodiment of the present application;

17 is a first schematic structural diagram of a control device according to an embodiment of the present application;

FIG. 18 is a second schematic structural diagram of a control device according to an embodiment of the present application.

detailed description

As shown in Figure 1, it is a schematic diagram of a wireless charging principle. Please continue to refer to FIG. 1, the wireless charging transmitting circuit 101 uses a primary series resonant capacitor Cp and a primary coil Lp in series, and the wireless charging receiving circuit 102 uses a secondary coil Ls and a secondary series resonant capacitor Cs in series. In the wireless charging system shown in FIG. 1, the transmission distance between the primary coil Lp and the secondary coil Ls is short. As the transmission distance between the primary coil Lp and the secondary coil Ls increases, the output power of the wireless charging receiving circuit 102 decreases rapidly. Therefore, the wireless charging receiving circuit 102 has poor anti-offset capability.

As shown in Figure 2, it is a schematic diagram of another type of wireless charging. Please continue to refer to FIG. 2, the wireless charging transmitting circuit 101 uses a primary series resonant capacitor Cp and a primary coil Lp in series, and the wireless charging receiving circuit 102 uses a secondary coil Ls and a secondary series resonant capacitor Cs in parallel. In the wireless charging system shown in FIG. 2, although the anti-offset capability of the wireless charging receiving circuit 102 is better than that of the wireless charging receiving circuit 102 shown in FIG. 1, due to the parallel compensation method, the output voltage near the resonance point has Resonant peaks, and the voltage change rate of the resonant peaks is large, so it is difficult to smoothly control the output voltage.

As shown in FIG. 3, an embodiment of the present application provides a wireless charging system, including a wireless charging transmitting circuit 101 and a wireless charging receiving circuit 102. The wireless charging receiving circuit and the wireless charging transmitting circuit are magnetically induced. For energy transfer. In the embodiment of the present application, the wireless charging transmitting circuit 101 may still use the primary series resonant capacitor Cp and the primary coil Lp in series, and the wireless charging receiving circuit 102 uses the secondary coil Ls and the secondary series resonant capacitor Cs in series and then connects the parallel resonant capacitor Cd in parallel. When the transmission distance between the primary coil Lp of the wireless charging transmitting circuit 101 and the secondary coil Ls of the wireless charging receiving circuit 102 increases, firstly, the method of reducing the alternating current frequency output from the wireless charging transmitting circuit 101 side in the prior art is used to compensate. The output voltage and output power of the wireless charging receiving circuit 102 decrease due to an increase in transmission distance. When the frequency of the AC power output from the wireless charging transmitting circuit 101 is reduced, the operating frequency coupled to the wireless charging receiving circuit 102 is reduced. When it is detected that the operating frequency coupled on the wireless charging receiving circuit 102 side is reduced to a certain degree, that is, when the transmission distance between the primary coil Lp and the secondary coil Ls is greatly increased, the output of the wireless charging transmitting circuit 101 side cannot be further reduced. The AC power frequency of the wireless charging receiving circuit 102 is increased by increasing the capacitance value of the parallel resonance capacitor Cd at this time to prevent the primary coil Lp of the wireless charging transmitting circuit 101 and the secondary coil of the wireless charging receiving circuit 102 from increasing. The transmission distance between Ls is increased, and the output voltage of the wireless charging receiving circuit is reduced.

In order to simulate the effect of the parallel resonant capacitor Cd more in line with the actual circuit, Fig. 4 further supplements Fig. 3: the line resistance Rp on the side of the wireless charging transmitting circuit 101, the equivalent leakage inductance Lkp of the primary magnetic coupling system, and the wireless The line resistance Rs on the side of the charging receiving circuit 102, the equivalent leakage inductance Lks of the secondary magnetic coupling system, and the filter capacitor Cf. And by way of example, the rectifier circuit 1021 is a rectifier bridge including four diodes. At this time, the load of the wireless charging receiving circuit 102 is a non-linear load. The schematic diagram shown in FIG. 4 is simulated, and the simulation diagram shown in FIG. 5 is obtained. The simulation result includes: the line current i1 of the wireless charging transmitting circuit 101 side, and the voltage of the AC power source Vs. FIG. 5 also shows the terminal voltage Vd of the parallel resonant capacitor Cd (that is, the input voltage of the rectifier circuit 1021), the line current i2 on the side of the wireless charging receiving circuit 102, and the line current i2 of the wireless charging receiving circuit 102 after the parallel resonant capacitor Cd participates in resonance. The input current i3 of the rectifier circuit 1021. Among them, the terminal voltage V2 of the parallel resonance capacitor Cd is alternating current, and V2 lags behind the power supply voltage V1 with a certain phase difference. The line current i2 on the side of the wireless charging receiving circuit 102 is an approximate sine wave, and the input current i3 of the rectifier circuit 1021 is a part of i2.

Factors affecting the output voltage of the wireless charging system include the operating frequency Fs of the wireless charging receiving circuit 102, the load RL, and the transmission distance between the primary coil Lp and the secondary coil Ls. Among them, as the transmission distance between the primary coil Lp and the secondary coil Ls increases, the equivalent leakage inductance LK of the magnetic coupling system between the primary coil Lp and the secondary coil Ls also increases, so the primary coil Lp and The equivalent leakage inductance LK of the magnetic coupling system between the secondary coils Ls equivalently replaces the transmission distance between the primary coil Lp and the secondary coil Ls.

As shown in FIG. 6, it is a schematic diagram of the output voltage of the wireless charging receiving circuit 102 changing with the parallel resonant capacitor Cd. At this time, the load RL is 10 ohms, the equivalent leakage inductance Lk of the magnetic coupling system is 7uH, and the operating frequency Fs is 140KHz, 145KHz, and 150KHz, respectively. It can be seen from this that when the operating frequency Fs is higher, the output voltage of the wireless charging receiving circuit 102 is lower. It can also be seen from Figure 6 that the output voltage first increases and then decreases as the capacitance of the parallel resonant capacitor Cd increases, that is, each operating frequency Fs curve includes a single peak point and a monotonically increasing interval, and each operating frequency Fs is taken. The intersection of the monotonically increasing interval of the curve gives the monotonically increasing interval [0, MAX1].

As shown in FIG. 7, it is a schematic diagram of the output voltage of another wireless charging receiving circuit 102 as a function of the parallel resonant capacitor Cd. At this time, the load RL is 10 ohms, the operating frequency Fs is 145KHz, and the equivalent leakage inductance Lk of the magnetic coupling system is 3uH, 5uH, 7uH, respectively. It can be seen from FIG. 7 that when the equivalent leakage inductance LK of the magnetic coupling system is higher (that is, the larger the distance between the wireless charging transmitting circuit 101 and the wireless charging receiving circuit 102 is, the larger the distance between the primary coil Lp and the secondary coil Ls. When the distance is larger), the output voltage of the wireless charging receiving circuit 102 is lower. Continuing to refer to FIG. 7, it is easy to know that the output voltage increases first and then decreases as the capacitance value of the parallel resonant capacitor Cd increases, that is, the equivalent leakage inductance Lk curve of each magnetic coupling system includes a single peak point and a monotonically increasing interval. The intersection of the monotonically increasing interval of the equivalent leakage inductance Lk curve of the magnetic coupling system gives the monotonically increasing interval [0, MAX2].

As shown in FIG. 8, it is a schematic diagram of the output voltage of the wireless charging receiving circuit 102 as a function of the parallel resonant capacitor Cd. At this time, the operating frequency Fs is 145KHz, the equivalent leakage inductance Lk of the magnetic coupling system is 7uH, and the load RL is 10Ω, 15Ω, and 20Ω, respectively. It can be seen from FIG. 8 that when the load RL is higher, the output voltage of the wireless charging receiving circuit 102 is higher. Continuing to refer to FIG. 8, it is easy to see that the output voltage increases first as the capacitance value of the parallel resonance capacitor Cd increases. Decrease, that is, each load RL curve includes a single peak point and a monotonically increasing interval. Take the intersection of the monotonically increasing interval of each load RL curve to obtain a monotonically increasing interval [0, MAX3].

With reference to Figs. 6-8, the intersection [0, MAX] of the monotonically increasing intervals [0, MAX1], [0, MAX2], [0, MAX3] can be used as the monotonically increasing capacitance of the parallel resonant capacitor Cd. Range, using MAX as the preset capacitance threshold, and when the parallel resonance capacitor Cd is within the monotonically increasing interval [0, MAX], the output voltage always monotonically increases with the increase of the parallel resonance capacitor Cd. During the increase of the parallel resonance capacitor Cd, As long as the preset capacitance threshold MAX is not exceeded, the output voltage of the wireless charging receiving circuit 102 can increase accordingly.

The capacitance range of the existing adjustable capacitors is relatively small, so the parallel resonant capacitor Cd can be equivalent to a plurality of subcapacitors C1-Cn in parallel, so that the capacitance value of each subcapacitor can be unlimited, and the equivalent parallel The capacitance value of the resonance capacitor Cd can also be adjusted within a wide range. Then each of the sub-capacitors C1-Cn is connected in series with each of the switchable controllable switching devices S1-Sn, and the parallel-connected sub-capacitance C1 is controlled by controlling the on and off of the switchable controllable switching devices S1-Sn. -The number of Cn, so as to achieve the purpose of adjusting the capacitance value of the equivalent parallel resonance capacitor Cd. However, as shown in Fig. 5, the terminal voltage V2 of the parallel resonant capacitor Cd is AC, and a single switch controllable switching device can only be turned off or on in a half cycle, and considering the circuit balancing effect, further, as shown in Fig. As shown in 10, each of the capacitors C1-Cn is further equivalent to a capacitor pair connected in series and having the same capacitance value, such as (C1, C1 ') ... (Cn, Cn'), and whether each capacitor is connected to the The wireless charging receiving circuit is still controlled by the on and off of a switch-controllable switching device, for example, whether the on-off and off-control capacitor C1 of the switch-controllable switching device S1 is connected to the wireless charging receiving circuit. Whether the on-off and off-control capacitor C1 of the controllable switching device S1 'is connected to the wireless charging receiving circuit. It should be noted that the driving signals of the switchable controllable switching devices S1 and S1 'are connected together, so it can be controlled whether the capacitors C1 and C1' are connected to the wireless charging receiving circuit at the same time, and other capacitors (C2, C2 ') …… (Cn, Cn ') is controlled in the same way.

The so-called "whether the capacitor is connected to the wireless charging receiving circuit" means that if the controllable switching device corresponding to the capacitor is turned on, the capacitor is connected to the wireless charging receiving circuit. The controllable switching device of the capacitor is turned off, so the capacitor is not connected to the wireless charging receiving circuit. When the capacitor is connected to the wireless charging receiving circuit, the capacitor is a part of the working capacitor of the wireless charging receiving circuit, that is, the capacitor can affect the output voltage and operating frequency of the wireless charging receiving circuit. When the capacitor is not connected to the wireless charging receiving circuit, the capacitor is not a part of the working capacitor of the wireless charging receiving circuit, that is, the capacitor cannot affect the output voltage and operating frequency of the wireless charging receiving circuit. In this case, the capacitor does not work, or does not actually participate in the work of the wireless charging receiving circuit.

For simplicity of description, the first terminal, the first input terminal, and the first output terminal involved in the embodiments of the present application are denoted by the reference numeral “1” in the device or circuit to which the drawings belong, and the second terminal and the second input The terminal and the second output terminal are indicated by the reference numeral "2" in the associated device or circuit in the drawing.

The wireless charging receiving circuit according to the embodiment of the present application may be applied to a terminal device. The terminal device includes: various handheld devices with wireless communication functions, vehicle-mounted devices, wearable devices, computing devices, or other processing devices connected to a wireless modem; it may also include a subscriber unit, and a cellular phone , Smart phone, wireless data card, personal digital assistant (PDA) computer, tablet computer, wireless modem (modem), handheld device (laptop computer), cordless Telephone (cordless phone) or wireless local loop (WLL) station, machine type communication (MTC) terminal, user equipment (UE), mobile station (MS), terminal Equipment (terminal device) or relay equipment (relay equipment). The relay device may be, for example, a 5G residential gateway (RG), or a wireless relay (radio relay).

As shown in FIG. 9, it is a schematic structural diagram of a terminal device according to an embodiment of the present application. In FIG. 9, a terminal device is taken as a mobile phone as an example, and a general hardware architecture of the mobile phone is described.

The mobile phone 900 may include radio frequency (RF) circuit 910, memory 920, other input devices 930, display screen 940, sensor 950, audio circuit 960, I / O subsystem 970, processor 980, and power supply 990 and other components . Those skilled in the art can understand that the structure of the mobile phone shown in the figure does not constitute a limitation on the mobile phone, and may include more or fewer parts than shown in the figure, or combine some parts, or disassemble some parts, or Different component arrangements. Those skilled in the art may understand that the display screen 940 belongs to a user interface (UI), and the display screen 940 may include a display panel 941 and a touch panel 942. Although not shown, the mobile phone may further include a functional module or device such as a camera, a Bluetooth module, and the details are not described herein again.

Further, the processor 980 is connected to the RF circuit 910, the memory 920, the audio circuit 960, the I / O subsystem 970, and the power source 990, respectively. The I / O subsystem 970 is connected to other input devices 930, a display screen 940, and a sensor 950, respectively. Among them, the RF circuit 910 may be used to receive and send signals during sending and receiving information or during a call. In particular, after receiving downlink information from the network side, it is sent to the processor 980 for processing. The memory 920 may be used to store software programs and modules. The processor 980 executes various functional applications and data processing of the mobile phone by running software programs and modules stored in the memory 920, for example, methods and functions of the terminal device in the embodiments of the present application. The other input device 930 may be used to receive inputted numeric or character information, and generate key signal inputs related to user settings and function control of the mobile phone. The display screen 940 may be used to display information input by the user or information provided to the user and various menus of the mobile phone, and may also accept user input. The sensor 950 may be a light sensor, a motion sensor, or other sensors. The audio circuit 960 may provide an audio interface between a user and a mobile phone. The I / O subsystem 970 is used to control input and output external devices. The external devices may include other device input controllers, sensor controllers, and display controllers. The processor 980 is a control center of the mobile phone 200, and uses various interfaces and lines to connect various parts of the entire mobile phone. By running or executing software programs and / or modules stored in the memory 920, and calling data stored in the memory 920, Perform various functions of the mobile phone 900 and process data to perform overall monitoring of the mobile phone.

The power supply 990 may include a battery and a wireless charging receiving circuit according to the embodiments of the present application. The power supply 990 is configured to supply power to the foregoing components. Preferably, the power supply can be logically connected to the processor 980 through the power management system, so as to implement functions such as management of charging, discharging, and power consumption through the power management system.

For the wireless charging receiving circuit according to the embodiment of the present application, the load RL includes the battery and the above-mentioned components except the power supply 990 in the terminal device. The wireless charging receiving circuit can obtain energy from the wireless charging transmitting circuit and supply power to the load RL.

As shown in FIG. 10, it is a schematic structural diagram of a wireless charging receiving circuit according to an embodiment of the present application. The wireless charging receiving circuit includes: N sets of capacitor switching networks 200, a rectifying circuit 300, and a controller CTRL, where N is an integer greater than or equal to 1. It should be noted that, for clarity of description, the drawings in the embodiments of the present application exemplarily show a plurality of sets of capacitive switch networks 200, but it is not intended to limit the use of a plurality of sets of capacitive switch networks 200.

A first terminal of each group of capacitor switch networks 200 is connected to a first input terminal of the rectifier circuit 300. A second terminal of each group of capacitor switch networks 200 is connected to a second input terminal of the rectifier circuit 300. That is, when the number of the capacitor switch networks 200 is more than one group, the capacitor switch networks 200 are connected in parallel, that is, the first ends of all the capacitor switch networks 200 are connected to the first input terminal of the rectifier circuit 300, and all the capacitor switches The second terminal of the network 200 is connected to the second input terminal of the rectifier circuit 300.

Exemplarily, one implementation manner of the rectification circuit 300 is a rectification bridge including four diodes (D1-D4) as shown in FIG. 10, and may also be other implementation manners, such as an integrated rectification chip and the like. Not limited.

Optionally, the wireless charging receiving circuit further includes a first filter capacitor Cf1, a first output terminal of the rectifier circuit 300 is connected to the first terminal of the first filter capacitor Cf1, and a second output terminal of the rectifier circuit 300 is connected to the first filter capacitor Cf1. The second end. The DC power output by the rectifier circuit 300 includes clutter. After being filtered by the first filter capacitor Cf1, it can supply power to the load RL.

The working principle of the capacitor switch network 200 is described below using the nth (1≤n≤N) group of capacitor switch networks 200 as an example:

The capacitor switching network 200 includes a first capacitor Cn, a second capacitor Cn ′, a first controllable switching device Sn, a second controllable switching device Sn ′, and a ground point M. The ground point M may be connected to the ground terminal GND of the rectifier circuit 300. . A first capacitor Cn located on one side of the ground point M and a first controllable switching device Sn are connected in series, and a second capacitor Cn ′ located on the other side of the ground point M and a second controllable switching device Sn are connected in series, wherein the same group of capacitor switches The capacitance value of the first capacitor Cn and the capacitance value of the second capacitor Cn ′ in the network 200 are equal. The foregoing limitation of the first capacitor Cn and the second capacitor Cn 'ensures that the potential of the ground point M of the capacitor switch network 200 is 0, otherwise, an unbalanced current will be generated at the ground point M.

The capacitance of the first capacitor Cn and the capacitance of the second capacitor Cn 'in the same group of capacitor switch networks 200 are equal. The capacitance of the first capacitor Cn between different groups of capacitor switch networks 200 may be different. In a possible implementation manner, the capacitance value of the first capacitor in the i + 1th group of capacitor switch networks is K times the capacitance value of the first capacitor in the ith group of capacitor switch networks, and the i + 1th group of capacitor switches The capacitance value of the second capacitor in the network is K times the capacitance value of the second capacitor in the i-th group of capacitor switching networks, i is an integer and 1≤i≤N-1, 1≤K≤10. For example, the capacitance value of the first capacitor and the second capacitor in the i-th capacitor switch network 200 is a * Ki, and the capacitance value of the first capacitor and the second capacitor in the i + 1-th capacitor switch network 200 are a * Ki + 1, a is the proportionality factor. Exemplarily, K may be 2.

Exemplarily, a series manner of the first capacitor Cn, the second capacitor Cn ′, the first controllable switching device Sn, and the second controllable switching device Sn ′ is shown in FIG. 10. The first capacitor Cn, the first The controllable switching device Sn, the second controllable switching device Sn ', and the second capacitor Cn' are connected in series in order. The ground point M of the capacitor switching network 200 is located between the first controllable switching device Sn and the second controllable switching device Sn '. The first terminal of the first capacitor Cn is connected to the first input terminal of the rectifier circuit 300, the second terminal of the first capacitor Cn is connected to the first terminal of the first controllable switching device Sn, and the second terminal of the first controllable switching device Sn The first terminal of the second controllable switching device Sn is connected, the second terminal of the second controllable switching device is connected to the first terminal of the second capacitor Cn ′, and the second terminal of the second capacitor Cn ′ is connected to the second terminal of the rectifier circuit 300 The input terminal, the common point between the second terminal of the first controllable switching device Sn and the first terminal of the second controllable switching device Sn ′ is grounded.

Exemplarily, another series manner of the first capacitor Cn, the second capacitor Cn ′, the first controllable switching device Sn, and the second controllable switching device Sn ′ is shown in FIG. 11. The first controllable switching device Sn The first capacitor Cn, the second capacitor Cn ′, and the second controllable switching device Sn ′ are connected in series. The ground point M of the capacitor switch network 200 ′ is located between the first capacitor Cn and the second capacitor Cn ′. The first terminal of the first controllable switching device Sn is connected to the first input terminal of the rectifier circuit 300, the second terminal of the first controllable switching device Sn is connected to the first terminal of the first capacitor Cn, and the second terminal of the first capacitor Cn Connected to the first terminal of the second capacitor Cn ', the second terminal of the second capacitor Cn' is connected to the first terminal of the second controllable switching device Sn ', and the second terminal of the second controllable switching device Sn' is connected to the rectifier circuit 300 The second input terminal, the common point between the second terminal of the first capacitor Cn and the first terminal of the second capacitor Cn ′ is grounded.

The controllable switching device (whether the first controllable switching device Sn or the second controllable switching device Sn ') includes a control terminal. When the control terminal of the controllable switching device is at the first level, the controllable switching device is turned on, and When the control terminal of the controllable switching device is at the second level, the controllable switching device is turned off, and by controlling the control terminal to a different level, the switch of the controllable switching device can be controlled.

Exemplarily, one implementation manner of the first controllable switching device Sn and the second controllable switching device Sn ′ is an N-type metal-oxide-semiconductor field effect transistor (metal-oxide- semiconductor field-effect transistor (MOSFET). The G terminal of the MOSFET is the control terminal. When the G terminal of the MOSFET is at the first level, the S terminal and the D terminal are turned on. When the G terminal of the MOSFET is at the second level, the S terminal and The D terminal is turned off. The first level is a high level, and the second level is a low level. It should be noted that the controllable switching device can also be implemented in other ways, such as P-type MOSFET, etc. The circuit can be applied to the embodiments of this application by adjusting the circuit accordingly. Therefore, this application does not limit the specific implementation of the controllable switching device. .

The controller CTRL includes N output terminals, and the N output terminals have a one-to-one correspondence with the N groups of capacitor switching networks. Each output terminal is used for the first controllable switching device Sn located in the corresponding group of capacitor switching networks. The control terminal is connected to the control terminal of the second controllable switching device Sn '. For example, the n-th output terminal of the controller CTRL is connected to the control terminal of the first controllable switching device Sn and the control terminal of the second controllable switching device Sn 'in the n-th group of capacitor switching networks, 1≤n≤N. When the nth output terminal outputs the first level, the first controllable switching device Sn and the second controllable switching device Sn ′ in the nth group of capacitor switching networks are turned on, so that the first capacitors Cn and The second capacitor Cn ′ is connected to the wireless charging receiving circuit, and the capacitance value of the parallel capacitor is increased. When the nth output terminal outputs the second level, the first controllable switching device Sn and the second controllable switching device Sn ′ in the nth group of capacitor switching networks are turned off, so that the first capacitors Cn and The second capacitor Cn 'is disconnected from the circuit, and the capacitance value of the parallel capacitor decreases.

The controller CTRL can share the ground with the capacitor switching network 200, so there is no need to increase the driving or auxiliary power supply isolation, which can simplify the circuit design.

The controller CTRL is used to:

The operating frequency of the AC voltage between the first input terminal and the second input terminal of the rectifier circuit 300 is obtained. For example, the controller CTRL may obtain the operating frequency through an integrated circuit (IC).

When the operating frequency is less than the first frequency threshold and the capacitance values of the first capacitor Cn and the second capacitor Cn ′ connected in the N-group capacitor switching network 200 are less than the preset capacitor threshold MAX, the output of each output terminal is adjusted by Level to control the on and off of the first controllable switching device Sn located in each group of capacitive switch network 200 and the on of the second controllable switching device Sn 'located in each group of capacitive switch network 200 And turn off, increase the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N-group capacitance switch network 200.

When the operating frequency is greater than the second frequency threshold, by adjusting the output level of each output terminal, the on and off of the first controllable switching device located in each group of capacitive switch networks is controlled, and each group is located in each group. The second controllable switching device in the capacitor switch network 200 is turned on and off to reduce the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N group of capacitor switch networks. The first frequency threshold is less than or equal to the second frequency threshold.

The controller CTRL may have a proportional integral calculator, and input the difference between the operating frequency and the preset frequency threshold into the proportional integral calculator to obtain a comparison result between the operating frequency and the preset frequency threshold.

As mentioned above, when the transmission distance increases, the AC voltage output from the wireless charging transmitting circuit 101 can be reduced to compensate for the decrease in the output voltage and output power of the wireless charging receiving circuit 102 due to the increased transmission distance. The working frequency of the wireless charging receiving circuit 102 side resonance will also decrease accordingly. Because the adjustment range of the AC frequency on the wireless charging transmitting circuit 101 side is limited, and the adjustment range of the resonance operating frequency on the wireless charging receiving circuit 102 side is also limited, when the operating frequency falls below the first frequency threshold, the parallel resonance capacitor is controlled to increase The capacitance value of Cd is used to compensate for the decrease in the output voltage and output power of the wireless charging receiving circuit. When the operating frequency rises above the second frequency threshold, the capacitance value of the parallel resonance capacitor Cd is controlled to reduce the wireless charging receiving circuit. The output voltage and output power are too large.

In a possible implementation manner, the controller may control the output terminal to output the first level or the second level according to the order of the capacitance values of the first capacitor and the second capacitor in the capacitor switching network 200 of each group. For example, as described above, assuming that the capacitance values of the first capacitor and the second capacitor in the i-th capacitor switching network 200 are a * Ki, the first capacitor and the second capacitor in the i + 1-th capacitor switching network 200 The capacitance value is a * Ki + 1. Before increasing the capacitance of the first capacitor and the second capacitor connected in the capacitor switch network, the first output terminal to the i-th output terminal of the controller outputs the first level, and the i + 1 output terminal to the N-th output Output the second level. When the condition for increasing the capacitance value is met, the first output terminal to the i + 1th output terminal of the controller outputs a first level, and the i + 2 output terminal to the Nth output terminal outputs a second level.

Alternatively, in another possible implementation manner, the controller may control the output terminal to output the first level or the second level according to the minimum step of the capacitance value. For example, as described above, assuming that the capacitance values of the first capacitor and the second capacitor in the i-th capacitor switching network 200 are a * Ki, the first capacitor and the second capacitor in the i + 1-th capacitor switching network 200 The capacitance value is a * Ki + 1. Before increasing the capacitance values of the first capacitor and the second capacitor connected in the capacitor switching network, the i-th output terminal of the controller outputs a first level, and the other output terminals output second levels. When the condition for increasing the capacitance value is met, the first output terminal and the i-th output terminal of the controller output a first level, and the other output terminals output a second level.

It should be noted that each time the capacitance value of the parallel resonance capacitor Cd is changed, the above control method is not limited.

Optionally, the wireless charging receiving circuit further includes a secondary coil Ls and a secondary series resonant capacitor Cs. The first end of the secondary coil Ls is connected to the first end of the secondary series resonance capacitor Cs, and the second end of the secondary series resonance capacitor Cs is connected to the first end of the N-group capacitor switching network 200 and the first input end of the rectifier circuit 300 . The second terminal of the secondary coil Ls is connected to the second terminal of the N-group capacitive switch network 200 and the second input terminal of the rectifier circuit 300.

The secondary coil Ls is used for coupling with the primary coil of the wireless charging transmitting circuit. The secondary series resonance capacitor Cs is used to generate series resonance with the secondary coil Ls. The N-group capacitor switching network 200 is used to generate parallel resonance with the secondary series resonant capacitor Cs and the secondary coil Ls.

The wireless charging receiving circuit provided in the embodiment of the present application adopts a parallel manner of N groups of capacitive switch networks, and controls on and off of the first controllable switching device located in each group of capacitive switch networks through a controller, and The on and off of the second controllable switching device located in each group of capacitor switch networks is used to control the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N group of capacitor switch networks. Further, when the working frequency of the alternating current input between the first input terminal and the second input terminal of the rectifier circuit is less than the first frequency threshold, controlling the increase of the capacitance of the capacitors connected to the wireless charging receiving circuit in the N-group capacitive switch network is increased. Capacitance. When the above-mentioned operating frequency is greater than the second frequency threshold, control is performed to reduce the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N-group capacitive switch network. That is, by controlling the on and off of the first controllable switching device and the second controllable switching device in each group of the N-capacitive switch network, it is possible to achieve increased access to wireless charging The capacitance of the receiving circuit or the capacitance of the wireless charging receiving circuit is reduced, so that the working frequency of the AC power input from the rectifier circuit on the wireless charging receiving circuit side can be adjusted. Therefore, the present application provides a circuit structure for conveniently controlling the operating frequency of the AC power input by the rectifier circuit.

Optionally, as shown in FIG. 12, the wireless charging receiving circuit may further include a direct current / direct current (DC / DC) step-down circuit 400.

The first terminal of the first filter capacitor Cf1 is connected to the first input terminal of the DC / DC step-down circuit 400, and the second terminal of the first filter capacitor Cf1 is connected to the second input terminal of the DC / DC step-down circuit 400. The first output terminal of the voltage reduction circuit 400 is connected to the first terminal of the load RL, and the second output terminal of the DC / DC step-down circuit 400 is connected to the second terminal of the load RL, and is used to reduce the voltage across the first filter capacitor Cf1 to increase Equivalent load impedance.

When adjusting the output power of the wireless charging receiving circuit, it is required to keep the output voltage as stable as possible. As mentioned earlier, when the capacitance value of the parallel resonance capacitor is increased, the voltage output by the rectifier circuit 300 will increase, so it needs to be adjusted accordingly. The DC / DC step-down circuit 400 stabilizes the voltage output by the DC / DC step-down circuit 400 (ie, the wireless charging receiving circuit).

Optionally, as shown in FIG. 12, the wireless charging receiving circuit may further include a first resistor R1 and a second resistor R2.

The first terminal of the first resistor R1 is connected between the first terminal of the first filter capacitor Cf1 and the first input terminal of the DC / DC step-down circuit 400 and the first output terminal of the rectifier circuit 300. The two terminals are connected to the first terminal of the second resistor R2, and the second terminal of the second resistor R2 is connected to the second output terminal of the rectifier circuit 300. The first terminal of the second resistor R1 is connected to the first input terminal of the controller CTRL. The first resistor R1 and the second resistor R2 are used to measure the voltage V3 output by the rectifier circuit 300.

Among them, the voltage at the second terminal of the first resistor R1 and the lead-out point at the first terminal of the second resistor R1 is Vx = V3 * R2 / (R1 + R2), which can be achieved by V3 = Vx * (R1 + R2) / R2 The voltage V3 output from the rectifier circuit 300 is reversed. It should be noted that the reason for measuring the voltage V3 by dividing the voltage is that the voltage V3 output by the rectifier circuit 300 is usually high and exceeds the withstand voltage value of the input terminal of the controller CTRL, so the lead-out point is divided by the first resistor and the second resistor The voltage drops below the withstand voltage of the CTRL input of the controller.

Optionally, if the DC / DC step-down circuit 400 does not include a filter capacitor, the wireless charging receiving circuit may further include a second filter capacitor Cf2. Connect the first terminal of the second filter capacitor Cf2 between the first output terminal of the DC / DC step-down circuit 400 and the first terminal of the load RL, and connect the second output terminal of the DC / DC step-down circuit 400 to the load RL. The second terminal of the second filter capacitor Cf2 is connected between the second terminals. The second filter capacitor Cf2 is used to filter the output current of the DC / DC step-down circuit 400.

Optionally, the wireless charging receiving circuit may further include a current sampling device CuSa. The current sampling device CuSa is located on the positive or ground line between the first filter capacitor Cf1 and the DC / DC step-down circuit 400. The current sampling device CuSa is connected to the second input terminal of the controller CTRL and is used to measure the output of the rectifier circuit 300. The current i4. The current sampling device CuSa can use the ratio of the voltage drop across the resistor to the resistance value to measure the current.

It should be noted that there may be other ways to measure the voltage V3 and current i4 output by the rectifier circuit, which is not limited in this application.

The controller CTRL can also be used:

Obtain the voltage V3 and current i4 output by the rectifier circuit. The output power P = V3 * i4 is obtained from the voltage V3 and the current i4.

For how to increase the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N-group capacitor switch network, please refer to the foregoing description, which will not be repeated here.

As shown in FIG. 13, a schematic diagram of a comparison of the offset capability and efficiency between the wireless charging receiving circuit and the conventional wireless charging receiving circuit according to the embodiment of the present application. The offset refers to a parallel plane or perpendicular to the plane where the primary coil or secondary coil is located. The change of the transmission distance on the surface is exemplified. In FIG. 13, the vertical surface is maintained at a transmission distance of 5 mm, and the parallel surface transmission distance is gradually increased from 0 mm as an example. It can be seen that the transmission efficiency of this scheme is higher than that of the traditional scheme, and the transmission efficiency is improved by about 10%. In addition, a certain transmission efficiency can still be ensured when the plane is offset by 8 mm with respect to the plane on which the primary coil or the secondary coil is located, while the traditional scheme cannot transmit when the deviation is 5 mm.

As shown in FIG. 14, it is a schematic diagram showing a relationship between a driving timing of a controllable switching device (such as a MOSFET) and an output power of a wireless charging receiving circuit according to an embodiment of the present application. Among them, the abscissa is time, and the unit is ms. S1 / S1 'indicates the control timing of the first controllable switching device S1 and the second controllable switching device S1' in the first group of capacitive switch networks, and S2 / S2 'indicates the first controllable switching device in the second group of capacitive switch networks The control timing of S2 and the second controllable switching device S2 ', S3 / S3' represents the control timing of the first controllable switching device S3 and the second controllable switching device S3 'in the third group of capacitor switching networks. The capacitance values of the first capacitor or the second capacitor in the first group of capacitor switch networks to the third group of capacitor switch networks are sequentially increased. G represents the decimal encoding corresponding to the binary encoding of S3 / S3 ', S2 / S2', and S1 / S1 ', S1 / S1' corresponds to the least significant bit of the binary, and S3 / S3 'corresponds to the most significant bit of the binary. For example, if S3 / S3 'is 1, S2 / S2' is 0, and S1 / S1 'is 1, the binary code is 101, and the corresponding decimal code G is 5. V_out represents the voltage output by the wireless charging receiving circuit, and i_out represents the current output by the wireless charging receiving circuit. This control method is actually the controller's minimum stepping mode (binary) of the capacitance value, and the control output terminal outputs the first level or the second level.

It can be seen from FIG. 14 that when the wireless charging receiving circuit works normally, V_out can always be stabilized at about 5.5V. As time goes by, the value of G gradually increases, and the capacitance value of the parallel resonance capacitor connected to the wireless charging receiving circuit gradually increases, and i_out gradually increases. When V_out is stable, the wireless charging receiving circuit outputs The power also gradually increases.

The above-mentioned circuit structure of the present application can also be applied to aspects such as offset loading, offset start, high and low frequency compatibility, and the like.

An embodiment of the present application provides a control method, which is applied to the foregoing wireless charging receiving circuit. As shown in FIG. 15, the method includes:

S1501. Obtain the operating frequency of the AC voltage between the first input terminal and the second input terminal of the rectifier circuit.

S1502: When the operating frequency is less than the first frequency threshold and the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N-group capacitive switch network is less than a preset capacitance threshold, by adjusting the output level of each output terminal, Control the on and off of the first controllable switching device located in each group of capacitive switch networks and the on and off of the second controllable switching device located in each group of capacitive switch networks to increase N groups The capacitance value of the capacitor connected to the wireless charging receiving circuit in the capacitor switch network.

S1503. In the case where the operating frequency is greater than the second frequency threshold, by adjusting the output level of each output terminal, control the on and off of the first controllable switching device located in each group of capacitor switching networks, and The second controllable switching device in a group of capacitor switch networks is turned on and off to reduce the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N group of capacitor switch networks.

Optionally, as shown in FIG. 16, the method may further include:

S1504: Obtain the voltage and current output by the rectifier circuit, and obtain the output power according to the voltage and current.

S1505. When the operating frequency is greater than or equal to the first frequency threshold and less than or equal to the second frequency threshold, the capacitance value of the capacitor connected to the wireless charging receiving circuit in the capacitor switch network is less than a preset capacitance threshold, and the output power is less than a preset In the case of a power threshold, by adjusting the output level of each output terminal, the on and off of the first controllable switching device located in each group of capacitive switch networks, and the first The two controllable switching devices are turned on and off to increase the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N-group capacitive switch network.

Regarding the above control method, specifically refer to the content of the controller described above, which will not be repeated here.

The embodiment of the present application further provides a control device, which can be used to execute the function of the controller in the foregoing implementation manner. In the embodiment of the present application, the control device may be divided into functional modules according to the foregoing method examples. For example, each functional module may be divided corresponding to each function, or two or more functions may be integrated into one processing module. The above integrated modules may be implemented in the form of hardware or software functional modules. It should be noted that the division of the modules in this application is schematic and is only a logical function division. There may be another division manner in actual implementation.

In a case where each functional module is divided corresponding to each function, FIG. 17 shows a possible structural schematic diagram of the control device involved in the foregoing embodiment. The control device 17 may include an obtaining unit 1711 and an adjusting unit 1712. The above units are used to support the control device to execute the related method in any one of the drawings in FIG. 15 to FIG. 16. The control device provided in this application is used to perform the function of the controller. Therefore, for the corresponding features and achievable beneficial effects, reference may be made to the beneficial effects in the corresponding implementation manners provided above, and details are not described herein again.

Exemplarily, the obtaining unit 1711 is configured to support the control device 17 to execute process S1501 in FIG. 15 or processes S1501 and S1504 in FIG. 16. The adjusting unit 1712 is configured to support the control device 17 to execute the processes S1502-S1503 in FIG. 15 or the processes S1502-S1503 and S1505 in FIG. Wherein, all relevant content of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, which will not be repeated here.

In a possible implementation manner, the obtaining unit 1711 is configured to obtain an operating frequency of an AC voltage between the first input terminal and the second input terminal of the rectifier circuit.

When the operating frequency is less than the first frequency threshold and the capacitance of the capacitors connected to the wireless charging receiving circuit in the N-group capacitive switch network is less than a preset capacitance threshold, the adjusting unit 1712 is configured to adjust the The output level controls the on and off of the first controllable switching device located in each group of capacitive switching networks, and the on and off of the second controllable switching device located in each group of capacitive switching networks, To increase the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N-group capacitive switch network.

When the operating frequency is greater than the second frequency threshold, the adjusting unit 1712 is further configured to control the on and off of the first controllable switching device located in each group of capacitor switching networks by adjusting the output level of each output terminal. And turning on and off of the second controllable switching device located in each group of capacitor switching networks to reduce the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N group of capacitor switching networks, where the first The frequency threshold is less than or equal to the second frequency threshold.

In a possible implementation manner, the obtaining unit 1711 is further configured to obtain the voltage and current output by the rectification circuit, and obtain the output power according to the voltage and current.

When the operating frequency is greater than or equal to the first frequency threshold and less than or equal to the second frequency threshold, the capacitance of the capacitor connected to the wireless charging receiving circuit in the capacitor switching network is less than a preset capacitance threshold, and the output power is less than the preset power threshold In the case of an adjustment unit 1712, it is also used to control the on and off of the first controllable switching device located in each group of capacitive switch networks by adjusting the output level of each output terminal, and each group of capacitive switches The second controllable switching device in the network is turned on and off to increase the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N-group capacitive switch network.

FIG. 18 is another schematic structural diagram of a control device involved in the foregoing embodiment. The control device 18 includes a processing module 1822 and a communication module 1823. Optionally, the control device 18 may further include a storage module 1821. The above modules are used to support the control device to execute the related methods in any of the drawings in FIG. 15 to FIG. 16.

In a possible manner, the processing module 1822 is configured to control and manage the actions of the control device 18 or execute corresponding processing functions, for example, the functions of the obtaining unit 1711 and the adjustment unit 1712. The communication module 1823 is used to support a function of the control device 18 communicating with other devices. The storage module 1821 is configured to store program code and / or data of the control device.

The processing module 1822 may be a processor or a controller. For example, the processing module 1822 may be a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), or an application-specific integrated circuit. integrated circuit (ASIC), field programmable gate array (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It may implement or execute various exemplary logical blocks, modules, and circuits described in connection with the present disclosure. The processor may also be a combination that implements computing functions, such as a combination including one or more microprocessors, a combination of a DSP and a microprocessor, and so on. The communication module 1823 may be a network interface or a communication interface. The storage module 1821 may be a memory.

In a possible manner, the processing module 1822 may be the processor 980 in FIG. 9, the communication module 1823 may be the RF circuit 910 in FIG. 9, and the storage module 1821 may be the memory 920 in FIG. 9. Among them, one or more programs are stored in the memory, and the one or more programs include instructions that, when executed by the control device, cause the control device to execute the related method in any one of FIGS. 15-16.

An embodiment of the present application further provides a control device, including: a processor and a memory, where the memory is used to store a program, and the processor calls the program stored in the memory, so that the control device executes any one of FIG. 15 to FIG. 16. Related methods in the figure.

An embodiment of the present application further provides a computer storage medium storing one or more programs, where a computer program is stored, and when the computer program is executed by a processor, the control device is caused to execute any one of the drawings in FIG. Related methods.

An embodiment of the present application further provides a computer program product containing instructions, and when the computer program product runs on a control device, the control device causes the control device to execute a related method in any of the drawings in FIG. 15 to FIG.

An embodiment of the present application provides a chip system. The chip system includes a processor, and is configured to support a control device to execute a related method in any one of FIG. 15 to FIG. 16. For example, the control device determines the sending end and the receiving end of the data stream communication according to the first instruction information and the second instruction information, where the first instruction information is used to indicate that the first device is a sending end, and the second instruction information is used to indicate the second The device is the receiving end, or the first instruction information is used to indicate that the first device is the receiving end, and the second instruction information is used to indicate that the second device is the sending end. The data stream includes first information identifying the data stream. It is used to instruct the sending end to send data through the data stream, and is also used to instruct the receiving end to receive data through the data stream; the control device obtains the bandwidth information of the data flow; the control device sends the data flow information and sends the bandwidth information, wherein the data flow information is used to indicate At least one of the port identifier of the sender and the port identifier of the receiver, the port identifier of the sender, the port identifier of the receiver, and bandwidth information are used to create a data stream. In a possible design, the chip system further includes a memory, and the memory is configured to store program instructions and data necessary for the terminal device. The chip system may include a chip, an integrated circuit, or a chip and other discrete devices, which are not specifically limited in the embodiments of the present application.

The control device, computer storage medium, computer program product, or chip system provided in this application is used to execute the control method provided by the controller. Therefore, for the beneficial effects that can be achieved, refer to the implementation provided above. The beneficial effects in the method are not repeated here.

It should be understood that, in the various embodiments of the present application, the size of the sequence numbers of the above processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not deal with the embodiments of the present application. The implementation process constitutes any limitation.

Those of ordinary skill in the art may realize that the units and algorithm steps of each example described in connection with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices, and units described above can refer to the corresponding processes in the foregoing method embodiments, and are not repeated here.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods may be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the unit is only a logical function division. In actual implementation, there may be another division manner. For example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, which may be electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, may be located in one place, or may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objective of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each of the units may exist separately physically, or two or more units may be integrated into one unit.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using a software program, it may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions according to the embodiments of the present application are wholly or partially generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be from a website site, a computer, a server, or a data center. Transmission to another website site, computer, server or data center via wired (such as coaxial cable, optical fiber, Digital Subscriber Line (DSL)) or wireless (such as infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device including one or more servers, data centers, and the like that can be integrated with the medium. The usable medium may be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk (Solid State Disk, SSD)), or the like.

The above is only a specific implementation of this application, but the scope of protection of this application is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in this application. It should be covered by the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

Claims

A wireless charging receiving circuit, comprising: N sets of capacitive switch networks, rectifier circuits and controllers, where N is an integer greater than or equal to 1; the first end of each set of capacitive switch networks is connected to the rectifier circuit. A first input terminal, and a second terminal of each group of capacitor switch networks is connected to a second input terminal of the rectifier circuit;

Each group of capacitor switching networks includes a first capacitor, a second capacitor, a first controllable switching device, a second controllable switching device, and a ground point. The first capacitor and the first capacitor located on one side of the ground point A controllable switching device is connected in series, and the second capacitor and the second controllable switching device located on the other side of the ground point are connected in series, wherein the capacitance value and The capacitances of the second capacitors are equal;

The controller includes N output terminals, and the N output terminals are in one-to-one correspondence with the N groups of capacitor switch networks, and each output terminal is used for the first possible switch located in the corresponding group of capacitor switch networks. The control terminal of the controllable switching device is connected to the control terminal of the second controllable switching device;

The controller is used for:

Obtaining an operating frequency of an AC voltage between a first input terminal and a second input terminal of the rectifier circuit;

When the working frequency is less than the first frequency threshold and the capacitance of the capacitors connected to the wireless charging receiving circuit in the N group of capacitor switching networks is less than a preset capacitance threshold, by adjusting the output voltage of each output terminal Level to control the on and off of the first controllable switching device located in each group of capacitive switching networks and the on and off of the second controllable switching device located in each group of capacitive switching networks to increase A capacitance value of a capacitor connected to the wireless charging receiving circuit in the N group of capacitor switch networks;

When the operating frequency is greater than the second frequency threshold, by adjusting the output level of each output terminal, the on and off of the first controllable switching device located in each group of capacitor switching networks is controlled, and The second controllable switching device in a group of capacitor switch networks is turned on and off to reduce the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N group of capacitor switch networks, wherein the first The frequency threshold is less than or equal to the second frequency threshold.
The wireless charging receiving circuit according to claim 1, wherein the controller is further configured to:

Acquiring the voltage and current output by the rectifier circuit, and obtaining output power according to the voltage and current;

When the operating frequency is greater than or equal to the first frequency threshold and less than or equal to the second frequency threshold, a capacitance value of a capacitor connected to the wireless charging receiving circuit in the capacitance switch network is smaller than the preset capacitance. A threshold value, and when the output power is less than a preset power threshold value, controlling the on and off of the first controllable switching device located in each group of capacitor switching networks by adjusting the output level of each output terminal, and The second controllable switching devices located in each group of capacitive switch networks are turned on and off to increase the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N group of capacitive switch networks.
The wireless charging receiving circuit according to claim 1 or 2, wherein a capacitance value of the first capacitor in the i + 1th group of capacitor switch networks is the first capacitor in the ith group of capacitor switch networks K times the capacitance value, i is an integer and 1≤i≤N-1, 1≤K≤10.
The wireless charging receiving circuit according to any one of claims 1-3, wherein the circuit further comprises a secondary coil and a secondary series resonant capacitor, and a first end of the secondary coil is connected to the secondary The first end of the series resonance capacitor, the second end of the secondary series resonance capacitor is connected to the first end of the N group of capacitor switching networks and the first input end of the rectifier circuit, and the second end of the secondary coil A terminal is connected to a second terminal of the N-group capacitor switch network and a second input terminal of the rectifier circuit.
The wireless charging receiving circuit according to any one of claims 1 to 4, further comprising a first filter capacitor, and a first output terminal of the rectifier circuit is connected to the first terminal of the first filter capacitor, so that The second output terminal of the rectifier circuit is connected to the second terminal of the first filter capacitor.
The wireless charging receiving circuit according to claim 5, further comprising a DC / DC step-down circuit;

A first terminal of the first filter capacitor is connected to a first input terminal of the DC / DC step-down circuit, and a second terminal of the first filter capacitor is connected to a second input terminal of the DC / DC step-down circuit, The first output terminal of the DC / DC step-down circuit is connected to the first end of the load, and the second output terminal of the DC / DC step-down circuit is connected to the second end of the load; the DC / DC step-down circuit Configured to reduce the voltage across the first filter capacitor.
The wireless charging receiving circuit according to any one of claims 1 to 6, further comprising a first resistor and a second resistor;

A first terminal of the first resistor is connected to a first output terminal of the rectifier circuit, a second terminal of the first resistor is connected to a first terminal of the second resistor, and a second terminal of the second resistor is connected A second output terminal of the rectifier circuit; a first terminal of the second resistor is connected to a first input terminal of the controller, and the first resistor and the second resistor are used to measure a voltage output by the rectifier circuit.
The wireless charging receiving circuit according to claim 6, further comprising a current sampling device;

The current sampling device is located on a positive line or a ground line between the first filter capacitor and the DC / DC step-down circuit, and the current sampling device is connected to a second input terminal of the controller for: Measure the current output by the rectifier circuit.
The wireless charging receiving circuit according to claim 6, further comprising a second filter capacitor;

A first terminal of the second filter capacitor is connected between a first output terminal of the DC / DC step-down circuit and a first terminal of the load, and a second output terminal of the DC / DC step-down circuit The second end of the second filter capacitor is connected to the second end of the load.
A control method, which is applied to the circuit according to any one of claims 1-9, and the method includes:

Obtaining an operating frequency of an AC voltage between the first input terminal and the second input terminal of the rectifier circuit;

When the working frequency is less than the first frequency threshold and the capacitance of the capacitors connected to the wireless charging receiving circuit in the N group of capacitor switching networks is less than a preset capacitance threshold, by adjusting the output level of each output terminal, Controlling the on and off of a first controllable switching device located in each group of capacitive switching networks and the on and off of a second controllable switching device located in each group of capacitive switching networks to increase the The capacitance value of the capacitors connected to the wireless charging receiving circuit in the N-group capacitor switch network;

When the operating frequency is greater than the second frequency threshold, by adjusting the output level of each output terminal, the on and off of the first controllable switching device located in each group of capacitor switching networks is controlled, and The second controllable switching device in a group of capacitor switch networks is turned on and off to reduce the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N group of capacitor switch networks, wherein the first The frequency threshold is less than or equal to the second frequency threshold.
The method according to claim 10, further comprising:

Acquiring the voltage and current output by the rectifier circuit, and obtaining output power according to the voltage and current;

When the operating frequency is greater than or equal to the first frequency threshold and less than or equal to the second frequency threshold, a capacitance value of a capacitor connected to the wireless charging receiving circuit in the capacitance switch network is smaller than the preset capacitance A threshold value, and when the output power is less than a preset power threshold value, controlling the on and off of the first controllable switching device located in each group of capacitor switching networks by adjusting the output level of each output terminal, and The second controllable switching devices located in each group of capacitive switch networks are turned on and off to increase the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N group of capacitive switch networks.
A control device, comprising:

An obtaining unit, configured to obtain an operating frequency of an AC voltage between a first input terminal and a second input terminal of the rectifier circuit;

When the working frequency is less than the first frequency threshold and the capacitance value of the capacitors connected to the wireless charging receiving circuit in the N-group capacitive switch network is less than a preset capacitance threshold, the adjusting unit is configured to adjust the output voltage of each output terminal. Level to control the on and off of the first controllable switching device located in each group of capacitive switching networks and the on and off of the second controllable switching device located in each group of capacitive switching networks to increase A capacitance value of a capacitor connected to the wireless charging receiving circuit in the N group of capacitor switch networks;

When the operating frequency is greater than a second frequency threshold, the adjusting unit is further configured to adjust an output level of each output terminal, and control the conduction of the first controllable switching device located in each group of capacitor switching networks. And off, as well as the on and off of the second controllable switching device located in each group of capacitive switch network, so as to reduce the capacitance value of the capacitor connected to the wireless charging receiving circuit in the N group of capacitive switch network , Wherein the first frequency threshold is less than or equal to the second frequency threshold.
The control device according to claim 12, wherein:

The obtaining unit is further configured to obtain a voltage and current output by the rectifier circuit, and obtain an output power according to the voltage and current;

When the operating frequency is greater than or equal to the first frequency threshold and less than or equal to the second frequency threshold, a capacitance value of a capacitor connected to the wireless charging receiving circuit in the capacitance switch network is smaller than the preset capacitance. When the threshold value is less than the preset power threshold, the adjusting unit is further configured to adjust the output level of each output terminal to control the first controllable switching device located in each group of capacitor switching networks. On and off, and on and off of a second controllable switching device located in each group of capacitive switch networks, increasing the capacitance of the capacitors connected to the wireless charging receiving circuit in the N group of capacitive switch networks value.
A terminal device, comprising the wireless charging receiving circuit according to any one of claims 1-9.
A storage medium, characterized in that a computer program is stored thereon, wherein the computer program implements the control method according to claim 10 or 11 when the computer program is executed by a processor.
A wireless charging system, comprising a wireless charging transmitting circuit and the wireless charging receiving circuit according to any one of claims 1-9, wherein magnetic induction is performed between the wireless charging receiving circuit and the wireless charging transmitting circuit. Way for energy transfer.